*{
    margin: 0;
    padding: 0;
}
body{
    background-color:#FFF;
}
.con{
    position: absolute;
    z-index: 0;
    top: 50%;
    margin-top: -51px;
    left: 50%;
    margin-left: -202px;
}
button{
    width:100px;
    height: 100px;
    background-color: #fff;
    border: 1px solid #ccc;
    float: left;
}
button:hover{
    background-color: #f5f5f5;
}

span{
    display: inline-block;
    width: 96%;
    height: 50px;
    margin-left: 2%;
    line-height: 50px;
    border-bottom: 1px solid #f5f5f5;
    text-align: center;
}
span:hover{
    background-color: #f5f5f5;
}

.bgDiv{
    width: 100%;
    height: 100%;
    background-color: #000;
    opacity: .5;
    position:fixed;
    display: none;
    z-index: 99;
    bottom: 0;
}
.leftNav{
    width: 50%;
    max-width: 400px;
    height: 100%;
    background-color: #fff;
    position: fixed;
    z-index: 999;
    top: 0;
    left: -50%;
}
.rightNav{
    width: 50%;
    max-width: 400px;
    height: 100%;
    background-color: #fff;
    position: fixed;
    z-index: 999;
    top: 0;
    right: -50%;
}
.upNav{
   width: 100%;
    height: 40%;
    background-color: #fff;
    position: fixed;
    z-index: 999;
    top: -40%;
}
.downNav{
    width: 100%;
    height: 40%;
    background-color: #fff;
    position: fixed;
    z-index: 999;
    bottom: -40%;
}

